<p>EARLIER THIS YEAR, thousands of people checked their e-mail and found a surprise: An American soldier needed help, and there was something in it for them. Their correspondent was a sergeant stationed in Iraq, he explained. He had accumulated millions in hundred-dollar bills—the older ones being phased out by the Treasury—from the cash brought into the country by the American occupation. The soldier needed to launder this money, fast, and needed a stateside bank account to do it. In return for a cut of the total, could he use yours?</p>